Video capture and production has evolved dramatically since the advent of movies and television. The introduction of magnetic tapes for recording, storage and playback of video was a dramatic advance, enabling a host of technologies such as the VCR that changed the way the world viewed entertainment.
The digital age has brought about changes in the video industry as well. Technologies such as digital tapes and DVDs allow video producers to store greater amounts of video data in a smaller physical space and in a durable format which, in theory, is immune to degradation over time. The ability to store greater amounts of video data is even more important now that high definition (HD) video is becoming more common. For example, a miniDV tape, depending on the type, currently can store up to approximately 70 gigabytes (GB) of video data, or about one hour of footage. A Blu-Ray digital video disk currently can store approximately 25 GB of video data. These advancing storage limits are propelling the acceptance of HD video, because HD video can take up four to five times the amount of room required for standard video.
New advances in random access devices such as solid state disks (SSD), an example of which is flash memory cards, are leading the way for video production to take another step forward. This application will discuss the use of flash memory, but it should be understood that the techniques described herein are not limited to any particular type of random access device, and any random-access device will suffice. The capacity of flash memory is growing at a high rate. While a 64 megabyte (MB) flash drive was standard just a few years ago, current high-end flash memory storage can approach approximately four GB. One such storage device is the P2 from Panasonic, which comprises several flash memory devices, configured in a Redundant Array of Independent Disks (RAID) Level 0, that act as one unit. While the storage capacity of random access devices, especially flash memory, does not yet equal that of standard magnetic tapes or digital video discs, a major advantage is that random access devices have virtually instantaneous access times.
The process of accessing video data from a tape is linear; that is, it proceeds in a straight line from start to finish. If one wishes to access video data stored in the middle of a tape, one must manually advance the tape to the spot marking the start of the desired data, begin processing the data in real time, and stop when the desired end is reached. With random access devices, a user can advance directly to the portion of the data to be accessed. Because access times are so fast, a user can appear to be accessing simultaneous streams of video data from the random access device because the accessing device can switch between accessing numerous portions of data stored on the random access device virtually instantaneously.
This generational shift in video media is especially pertinent in television media production. A current approach is to record hours of footage on video tapes, either analog or digital. The video data on these tapes is transferred to hard drives for use in computerized editing stations such as Apple's Final Cut Pro, Adobe Premiere, or a combination hardware and software solution such as Avid.
There are generally two different workflows for working with video data: an online, or full-resolution workflow, and an offline, or low-resolution workflow. The low-resolution workflow is often used because video producers have limited hard drive space and massive amounts of video footage. In the low-resolution workflow, the producers bring a low resolution version of the footage “offline.” This involves transferring the video into a smaller footprint format and does not take as long as transferring the video at full resolution.
The low-resolution footage is then edited. The edits may involve reordering portions of footage, cutting between sections of footage, overlaying graphics, and similar tasks. Once the production tasks are finished using the low-resolution footage, the producers move to a full-resolution workflow, which involves moving to an “online” editing system that has much greater disk storage space. The video footage needed for the final version, that is, the footage that will constitute the final version, is recaptured at a higher resolution, often the native or full resolution.
After the video editing process is done, the original tapes are locked and never erased, because producers want to have the option of going back to recapture in high resolution the footage that was not captured before. The tapes also serve as a master copy.
A project file is generally a list of video files comprising a video project along with characteristics of the video files, such as start and end times of the video files within the project, filters applied to the video data within the files, transitions applied, and other aspects of the video files and the project itself. The project file is generally kept in hard drive storage because it is very small. If producers ever want to go back and recapture the footage in the project, they may use the project file to identify portions of video data needed to be recaptured and this data may be used to automatically recapture only the necessary portions of video data.
A drawback to the above approach, as it pertains to video captured on random access devices, is that random access devices are very expensive relative to tapes and other forms of storage media. Thus, it is cost-prohibitive to store video data on random access devices, and then store the random access devices in a library for possible future retrieval of the video data.
The inherent versatility of random access devices, namely their ability to be erased quickly and innumerable times, does not lend itself to long-term archival purposes. Rather, the inherent characteristics of random access devices make it ideal for reuse. For example, unlike tapes, there is no physical wear by reshooting on the same random access device over and over. As a result, producers want to shoot footage on random access devices, delete the footage after capturing it in higher-definition to long-term storage, and reuse the random access device for the next project.
This desire to erase footage in order to reuse the random access device causes problems if the erased footage had not been fully captured; for example, of the footage on a random access device, only a fraction may have been captured in full-definition to long-term storage, such as digital video tapes. If the footage is erased without storing it to long-term storage, and a future need arises for the non-captured full-definition footage, then there is nothing that can be done.
Therefore, a need exists for a technique that allows for the storing, accessing, identifying and displaying of information about the status of digital media files that may have been captured to storage devices.
The approaches described in this section are approaches that could be pursued, but not necessarily approaches that have been previously conceived or pursued. Therefore, unless otherwise indicated, it should not be assumed that any of the approaches described in this section qualify as prior art merely by virtue of their inclusion in this section.